What is described does work. I however, spent the 80 or so bucks on a reset tool so I wouldn't have to count pins and seconds. The reset tools can be found on ebay and such, and all they do is basically what e39 said, just electronically. Option number 2, just costs a few bucks.

These tools are not necessary for the e39 series because i reset them myself from the left reset button on my instrument cluster! just go to www.alldatapro.com and search for "resetting the service interval indicator(sii)